The invention generally relates to monitoring or indicating the opening of an automatic safety control switch connected to protect electrical equipment from overload, and more particularly to visually indicate by mechanical means an initial opening of an automatically resetting safety control switch.
The best prior art is my U.S. Pat. No. 4,092,625 issued May 30, 1978 for a monitoring device for similar purpose that disclosed the combustion of a chemical mixture triggered by the opening of the safety control switch, which being automatic, could close with no indication that it was ever open. Cited as the closest art to my previous invention were the following U.S. patents: K. M. Kiel U.S. Pat. No. 2,712,575 for a squib switch for use with proximity fuzes of projectiles; R. C. Evans et al U.S. Pat. No. 2,790,877 for a switch actuated by a chemical change; I. Kabik U.S. Pat. No. 3,118,994 for a continuously adjustable ignition type time delay switch; and Charles R. Olsen U.S. Pat. No. 3,948,143 for an electropyrotechnic link that is activated by an electrical signal to release an object on command, such as a springler system, etc.
The invention is not a switch nor a safety device such as a fuse or a circuit breaker. It is specially designed to indicate casualty sufficient to activate the safety control switch which might have self-corrected with no indication of having been activated.